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Proper Upgrade List for Transmission

28923 Views 2 Replies 3 Participants Last post by  country_hick
I told everyone that I would work on a upgrade list for the transmissions in our trucks, so here is how and why we recommend the parts we do:

First for a Truck that's transmission is working fine but wants to make it tougher:

Trucks making stock-100hp over stock:
1. Good shift kit, the reason we recommend upgrading to the shift kit is for the increased line pressure, which help the entire transmission. (for those who don't feel confident building there own VB you can also get a full VB from most companies) Try and stay to a more custom Shift kit as you will get better results than a one size fits all.

2. Billet Servo and Billet accumulator, these parts make a great upgrade as they help seal the transmission. The factory servo and accumulator generally have up to 30% leakage which is a big contributor to the 2nd gear failures.

3. A good TC, whether it be a Billet Single or Billet 3 Disk, this is more a option at this power lever but not necessary.

Trucks making 100hp-200hp over stock*you should add all the above parts, plus the following

4. HD Master Kit, I would use a Heavy Duty Master kit, one that increases the clutch count and gives you all the required parts to achieve the proper clearances. For the most part any good aftermarket company should have a good kit for this application, try and stay away from the E-Bay type of kits as I have seen a few, and they are far from a smooth install. Also make sure who ever you get the kit from can support the product, as we have had several people call with kits they got elsewhere that couldn't get help, and it's hard for any of the aftermarket companies to help with a kit they don't build.

5. Billet 3 Disk TC, I would personally go with a Billet 3 Disk TC, as they are much stronger, especially at the lower RPM's. Plus with some companies having the technology now to offer Billet Dampning systems it makes the lock-up engagement much smoother and much easier on the Input Shaft.

Trucks making 200+hp over stock or towing over 10 000lbs *you should add all the above parts, plus the following

6. Billet Input Shaft, I recommend this upgrade to anyone that can swing the extra $$$ for this part, as it's really good insurance not matter what you do with the truck, but once you reach this power level it should be done. Remeber there are several different Billet Input Shafts and some are better than others, so make sure you talk with vendor that you think has done there homework and not just the cheaper, because I can tell you from experience there is a difference.

Upgrades that are most application based than power based:
- Billet Output Shaft: This upgrade is really only needed for guys using 4wd for boost launching, Sled Pulling, Serious offroading. It doesn't really matter how much HP you make it, if you don't use 4wd hard you aren't putting much load on it.

- Billet Flexplate: This is one of those parts that I tell my customers it's like gambling, I can't honestly say who needs one and who doesn't. I have seen several stock trucks break them, while seeing lots of guys with tons of HP not break them. It's one of those parts that it seems luck has a lot to do with. For the cost I recommend anyone doing it that can swing the $$$$.

- Billet Band Struts, Billet Band Anchors should be added to all transmission when upgrading as they cost less that $50 for the pair and if the stock one breaks it will do $1000's in damage most of the time.

Please if you have any question as to pricing or applications, please message me our your chosen vendor as per site rules I can't post pricing.

One thing that I have learned over the years is that you can build a transmission for the price you want and have it do what you want it to do, if you do some home work. In the transmission business you don't have to spend the most to get the best.
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sticky for the auto guys
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When do you recommend upgrading the planetary gearsets? The aluminum housing on one could break at some point. Also, the 47RE has a smaller tooth count in he steel gearsets than the 48RE does. Does it make sense to replace them all at some power or towing level?
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